The proposed study extends a successful nursing intervention for breast cancer patients to low income younger anglo and minority women. The intervention would teach these women uncertainty management as a means of enhancing self-care and self-help behaviors. The purposes of this study are: 1) to determine the effectiveness of an uncertainty management intervention delivered by a nurse-client manager by telephone in increasing cancer knowledge, enhancing self-care, promoting self-help respond, and improving or maintaining life quality among younger, low income anglo, African-American, and Mexican-American women receiving treatment for breast cancer; 2) to determine whether person factors (including education, uncertainty, uncertainty management, and satisfaction with health care), disease factors (including type of medical treatment, number of types of treatments, recurrence, metastases, and staging), contextual factors (including sources of information, social support, place receiving treatment and access to treatment) and time enhance or limit self-care/self-help activities, cancer knowledge and life quality of women during cancer treatment, and 3) to estimate the cost effectiveness of the intervention. The design is a 2 X 3 repeated measures design with two levels of treatment (uncertainty management and natural control condition) crossed with three levels of ethnicity (anglo, African-American and Mexican- American). The measures are taken at baseline and 4 and 7 months post baseline. The intervention runs for 10 weeks and is delivered by weekly telephone calls. The intervention is based on the Uncertainty in Illness Theory and on the Self-Help Model that depicts learned response to chronic illness experience. The intervention has been modified from the original protocol to specifically address concerns of the younger woman. Multivariate models will be used to test for intervention effects, efficiency, pattern of change and durability of change over time relative to four outcomes, self-care, self-help, cancer knowledge and life quality. Analyses includes testing both direct and interactive effects of groups of variables classified as person, disease, and contextual variables that have either a moderation or mediation effect on outcome variables. Cost effectiveness analytic techniques will be used to calculate ratios of change in the outcome measures achieved relative to costs and utilization level within the subject groups.